I've been doing some playtesting on the large map.
Playing marathon, I've consistantly been having civs fall to barbarian horsemen. Last game, it was 3 civs by 800 AD. And more were going to fall, judging from the hordes encroaching on their territory.
I've been investigating the problem, and here's some of what I found.
First, the strengths...
Horse Archer... +100% vrs melee, -20% city attack, Str 5... adjusted to 8 against melee in a city.
Warrior... +25% city defense, +25% assuming it's been fortified, Str 2... adjusted to 3 when defending in a city.
Obviously, there is no contest between the Warrior and the Horse Archer at 8:3 odds (lacking a wall). Even the Warrior upgrade, Militia, fails at 8:7.5 odds.
The Spearman fares better. Against Horse Archer, when defending in a city, it defends at 9:8... much better odds than a Warrior.
The Archer defends at 5 when fortified in a city, but the Horse Archer Str against a nonmelee unit goes down to 4 vrs a city. 5:4. Archer wins.
The Swordsman defends at 7.5:8, a slight disadvantage. The Axeman defends at 6.25:8, slightly worse.
Given these facts, It looks like the AI ought to be producing units that adequately defend against the Horse Archers... Spearman and Archer. So what's going wrong.
I believe the problem is in the Unit AI. Archer had a AI_Attack, Spearman has AI_Counter (whatever that means). The only unit with AI_Defend is the Warrior, the absolute worst defender against Horse Archers.
How to dorrect this...
-the city attack negative for Horse Archer could be increased... at -50% it would still devestate Warriors at 7.5:3. At -100% it's still 5:3.
-we could lower the anti-melee % of horse archer. at only 50%, the odds infavour of the Horse Archer vrs Warrior at 6.5:1
-we could do both... -100% vrs city, and +50% vrs melee... this would be 2.5:3 in favour of the warrior.
-but how would this effect other combats...
Horse Archer vrs Spear in city would be ridiculous. 2.5 to 9 for the Spearman. vrs Archer it would be 2.5 to 5 in favour of the Archer. Similarly Axeman and Swordsman both triumph.
So the imbalance goes the other way then.
I'm really not certain how to solve this problem. The unit strengths need to be examined, in light of paper rock scissors concept. We could change Spearman or Archer AI to defend, but this leaves no role for the Warrior as it's best in defense, but rather poor at it. We could fiddle with the Warriors city defense %, but its str is so low at 2, that rather high percentages would be needed to make a difference. Some combination of all these will have to be worked out I suppose.
Anyhow, just a few thoughts. The barbarian horsearcher problem does not seem to be so great at normal speed. I've not tested that enough, though... anyone else notice these sorts of problems?